<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    .parent{
        width: 100%;
        height: 500px;
        background-color: #719b7a;
        margin-top: 100px;
        overflow: hidden;
    }
    .child{
        width: 100%;
        height: 200px;
        background-color: #9c539e;
        margin-top: 50px;
    }
</style>
<body>
    <div class="parent">
        <div class="child"></div>
    </div>
</body>
</html>